@article{28017,
  abstract     = {{Processing aluminum alloys employing powder bed fusion of metals (PBF-LB/M) is becoming more attractive for the industry, especially if lightweight applications are needed. Unfortunately, high-strength aluminum alloys such as AA7075 are prone to hot cracking during PBF-LB/M, as well as welding. Both a large solidification range promoted by the alloying elements zinc and copper and a high thermal gradient accompanied with the manufacturing process conditions lead to or favor hot cracking. In the present study, a simple method for modifying the powder surface with titanium carbide nanoparticles (NPs) as a nucleating agent is aimed. The effect on the microstructure with different amounts of the nucleating agent is shown. For the aluminum alloy 7075 with 2.5 ma% titanium carbide nanoparticles, manufactured via PBF-LB/M, crack-free samples with a refined microstructure having no discernible melt pool boundaries and columnar grains are observed. After using a two-step ageing heat treatment, ultimate tensile strengths up to 465 MPa and an 8.9% elongation at break are achieved. Furthermore, it is demonstrated that not all nanoparticles used remain in the melt pool during PBF-LB/M.}},
  author       = {{Heiland, Steffen and Milkereit, Benjamin and Hoyer, Kay-Peter and Zhuravlev, Evgeny and Keßler, Olaf and Schaper, Mirko}},
  journal      = {{Materials}},
  keywords     = {{grain refinement, crack reduction, laser beam melting, aluminum alloy, titanium carbide, nanoparticle, PBF-LB/M}},
  title        = {{{Requirements for Processing High-Strength AlZnMgCu Alloys with PBF-LB/M to Achieve Crack-Free and Dense Parts}}},
  doi          = {{https://doi.org/10.3390/ma14237190}},
  year         = {{2021}},
}

@article{24086,
  abstract     = {{Laser beam melting (LBM) is an advanced manufacturing technology providing
special features and the possibility to produce complex and individual parts directly
from a CAD model. TiAl6V4 is the most common used titanium alloy particularly
in biomedical applications. TiAl6Nb7 shows promising improvements especially
regarding biocompatible properties due to the substitution of the hazardous
vanadium. This work focuses on the examination of laser beam melted TiAl6Nb7.
For microstructural investigation scanning electron microscopy including energydispersive
x-ray spectroscopy as well as electron backscatter diffraction are utilized.
The laser beam melted related acicular microstructure as well as the corresponding
mechanical properties, which are determined by hardness measurements
and tensile tests, are investigated. The laser beam melted alloy meets,
except of breaking elongation A, the mechanical demands like ultimate tensile
strength Rm, yield strength Rp0.2, Vickers hardness HV of international standard
ISO 5832-11. Next steps contain comparison between TiAl6Nb7 and TiAl6V4 in
different conditions. Further investigations aim at improving mechanical properties
of TiAl6Nb7 by heat treatments and assessment of their influence on the microstructure
as well as examination regarding the corrosive behavior in human bodylike
conditions.}},
  author       = {{Hein, Maxwell and Hoyer, Kay-Peter and Schaper, Mirko}},
  issn         = {{0933-5137}},
  journal      = {{Materialwissenschaft und Werkstofftechnik}},
  keywords     = {{Laser beam melting, titanium alloy, TiAl6Nb7, biomedical engineering, implants}},
  pages        = {{703--716}},
  title        = {{{Additively processed TiAl6Nb7 alloy for biomedical applications}}},
  doi          = {{10.1002/mawe.202000288}},
  volume       = {{52}},
  year         = {{2021}},
}